It’s definitely Casper, the dog from the story the other commenter linked, but some of the people retelling the story already exaggerated it, so depending on where you read it, there might as well have been a “trail of dead pack members” or something similar in the retold story.

For example: dailystar.co.uk/…/brave-sheepdog-left-bloodied-af…

Casper, a sheepdog from Georgia in the United States, left a trail of blood and parts of his tail behind him as he disappeared for two days after the battle erupted whilst he was on guard.

Or one of the reddit posts relatively high up in the search results:

“…they believed he was tracking the remaining coyotes and finishing the job”

All of the actually trustworthy news outlets only mention that he was gone for two days and then taken to the vet once he returned, but not more than that.